Previous findings of the lead inventor showed that small molecule reductive alkylating agents called pyrrolobenzimidazoles or PBIs (Chart 1) show a high degree of specific cytotoxicity for some cancers. {Skibo, E. B. Pyrrolobenzimidazoles in cancer treatment. Expert. Opin. Ther. Patents. 1998, 8, 673-701} This specificity is very likely due to the presence of the two-electron reducing enzyme DT-diaphorase, which reduces the PBI in these cells. {Zhou, R.; Skibo, E. B. Chemistry of the Pyrrolo[1,2-α]benzimidazole Antitumor Agents: Influence of the 7-Substituent on the Ability to Alkylate DNA and Inhibit Topoisomerase II. J.Med.Chem. 1996, 39, 4321-4331} {Skibo, E. S.; Gordon, S.; Bess, L.; Boruah, R.; Heileman, J. Studies of Pyrrolo[1,2-α]benzimidazole Quinone DT-Diaphorase Substrate Activity, Topoisomerase II Inhibition Activity, and DNA Reductive Alkylation. J. Med. Chem. 1997, 40, 1327-1339} Reduction of the PBI to the corresponding hydroquinone causes the aziridine nitrogen to become more basic resulting in protonation and nucleophilic attack (alkylation). Similarly, indoloquinones such as mitomycin C {Spanswick, V. J.; Cummings, J.; Smyth, J. F. Current issues in the enzymology of mitomycin C metabolic activation. Gen.Pharmacol. 1998, 31, 539-544} and EO9, {Bailey, S. M.; Lewis, A. D.; Knox, R. J.; Patterson, L. H.; Fisher, G. R.; Workman, P. Reduction of the indoloquinone anticancer drug EO9 by purified DT-diaphorase: A detailed kinetic study and analysis of metabolites. Biochem.Pharmacol. 1998, 56, 613-621} (Chart 1) require two—electron reductive activation by DT-diaphorase. 